Advertisement

Plant Ecology

, Volume 215, Issue 1, pp 83–95 | Cite as

Changing dominance of key plant species across a Mediterranean climate region: implications for fuel types and future fire regimes

  • Rebecca K. Gibson
  • Ross A. Bradstock
  • Trent D. Penman
  • David A. Keith
  • Don A. Driscoll
Article

Abstract

Herbaceous and woody plants represent different fuel types in flammable ecosystems, due to contrasting patterns of growth and flammability in response to productivity (moisture availability). However, other factors, such as soil type, fire regimes and competitive interactions may also influence the relative composition of herbaceous and woody plants within a community. The Mediterranean climate region of south eastern Australia is transitional between two contrasting fuel systems; herbaceous dominated in the dry north, versus woody plant dominated shrublands in the relatively moist south. Across the rainfall gradient of the region, there are confounded changes in dominant soil types and fire frequency. We used model-subset selection using Akaike’s Information Criterion to examine potential driving mechanisms of community compositional change from herbaceous (e.g. Triodia scariosa, Austrostipa sp.) to woody plants (e.g. Beyeria opaca, Leptospermum coriaceum, Acacia ligulata) by measuring relative cover across combinations of rainfall, time since the last fire (TSF) and soil type. We examined the relative influence of environmental versus competitive interactions on determining the cover of perennial hummock grass, T. scariosa, and co-occurring woody shrubs. Rainfall and soil types, rather than competition, were the over-arching determinants of the relative cover of grasses and shrubs. Given the sensitivity to rainfall, our results indicate there is strong potential for the nature of fuel, flammability and fire regimes to be altered in the future via climate change in this region.

Keywords

Fuel types Herbaceous and woody plants Productivity gradient Mediterranean climate region Fire regimes Climate change 

Notes

Acknowledgments

The study was funded by an ARC Linkage Grant (LP0776604) with Department of Environment, Water and Natural Resources (SA) the Native Vegetation Council (SA), SA Museum and the Office of Environment and Heritage (NSW) as project partners. Thanks to the volunteers who helped with field work.

References

  1. Archibald S, Roy D, van Wilgen B, Scholes R (2009) What limits fire? An examination of drivers of burnt area in Southern Africa. Glob Change Biol 15:613–630CrossRefGoogle Scholar
  2. Blackburn G, Wright MJ (1989) Soils. In: Noble JC, Bradstock RA (eds) Mediterranean landscapes in Australia: mallee ecosystems and their management. CSIRO Australia, Melbourne, pp 35–53 Google Scholar
  3. BOM (2013) La Niña—detailed Australian analysis. Bureau of Meteorology, Commonwealth of AustraliaGoogle Scholar
  4. Bond W, Keeley J (2005) Fire as a global ‘herbivore’: the ecology and evolution of flammable ecosystems. Trends Ecol Evol 20:387–394PubMedCrossRefGoogle Scholar
  5. Bradstock R (2010) A biogeographic model of fire regimes in Australia: contemporary and future implications. Glob Ecol Biogeogr 19:145–158CrossRefGoogle Scholar
  6. Bradstock RA, Cohn JS (2002) Fire regimes and biodiversity in semi-arid mallee ecosystems. In: Bradstock RA, Gill AM, Williams JE (eds) Flammable Australia: the fire regimes and biodiversity of a continent. Cambridge University Press, Cambridge, pp 238–258Google Scholar
  7. Burnham K, Anderson D (2002) Model selection and multimodel inference: a practical information-theoretic approach. Springer-Verlag, New YorkGoogle Scholar
  8. Carrera AL, Sain CL, Bertiller MB (2000) Patterns of nitrogen conservation in shrubs and grasses in the Patagonian Monte, Argentina. Plant Soil 224:185–193CrossRefGoogle Scholar
  9. Clarke PJ, Lawes MJ, Midgley JJ, Lamont BB, Ojeda F, Burrows GE, Enright NJ, Knox KJE (2013) Resprouting as a key functional trait: how buds, protection and resources drive persistence after fire. New Phytol 197:19–35PubMedCrossRefGoogle Scholar
  10. Collins D (2000) Annual temperature summary: Australia records warmest decade. Climatic Change Newsletter 12Google Scholar
  11. February EC, Allsopp N, Shabane T, Hattas D (2011) Coexistence of a C4 grass and a leaf succulent shrub in an arid ecosystem. The relationship between rooting depth, water and nitrogen. Plant Soil 349:253–260CrossRefGoogle Scholar
  12. Fowler N (1986) The role of competition in plant communities in arid and semiarid regions. Annu Rev Ecol Syst 17:89–110CrossRefGoogle Scholar
  13. Hutchinson M, McIntyre S, Hobbs R, Stein J, Garnett S, Kinlock J (2005) Integrating a global agro-climatic classification with bioregional boundaries in Australia. Glob Ecol Biogeogr 14:197–212CrossRefGoogle Scholar
  14. Keeley JE, Pausas JG, Rundel PW, Bond WJ, Bradstock RA (2011) Fire as an evolutionary pressure shaping plant traits. Trends Plant Sci 16:406–411PubMedCrossRefGoogle Scholar
  15. Keeley JE, Bond W, Bradstock R, Pausas JG, Rundel P (2012) Fire in Mediterranean climate ecosystems: ecology, evolution and management. Cambridge University Press, CambridgeGoogle Scholar
  16. Lehmann CER, Archibald SA, Hoffmann WA, Bond WJ (2011) Deciphering the distribution of the savanna biome. New Phytol 191:197–209PubMedCrossRefGoogle Scholar
  17. Letnic M, Dickman CR (2006) Boom means bust: interactions between the El Nino/Southern Oscillation (ENSO), rainfall and the processes threatening mammal species in arid Australia. Biodivers Conserv 15:3847–3880CrossRefGoogle Scholar
  18. MacNally R (2000) Regression and model-building in conservation biology, biogeography and ecology: the distinction between—and reconciliation of—‘predictive’ and ‘explanatory’ models. Biodivers Conserv 9:655–671CrossRefGoogle Scholar
  19. Murphy BP, Bowman DMJS (2007) Seasonal water availability predicts the relative abundance of C3 and C4 grasses in Australia. Glob Ecol Biogeogr 16:160–169CrossRefGoogle Scholar
  20. Murphy BP, Bradstock RA, Boer MM, Carter J, Cary GJ, Cochrane MA, Fensham RJ, Russell-Smith J, Williamson GJ, Bowman DMJS (2013) Fire regimes of Australia: a pyrogeographic model system. J Biogeogr 40:1048–1058CrossRefGoogle Scholar
  21. Noble JC (1989) Fire studies in mallee (Eucalyptus spp.) communities of western New South Wales: the effects of fires applied in different seasons on herbage productivity and their implications for management. Aust J Ecol 14:169–187CrossRefGoogle Scholar
  22. Ogle K, Reynolds JF (2004) Plant responses to precipitation in desert ecosystems: integrating funcitonal types, pulses, thresholds and delays. Oecologia 141:282–294PubMedCrossRefGoogle Scholar
  23. Pausas J, Bradstock R (2007) Fire persistence traits of plants along a productivity and disturbance gradient in mediterranean shrublands of south-east Australia. Glob Ecol Biogeogr 16:330–340CrossRefGoogle Scholar
  24. Pausas J, Paula S (2012) Fuel shapes the fire-climate relationship: evidence from Mediterranean ecosystems. Glob Ecol Biogeogr 21:1074–1082CrossRefGoogle Scholar
  25. Pielou EC (1962) The use of plant-to-neighbour distances for the detection of competition. J Ecol 50:357–367CrossRefGoogle Scholar
  26. Pucko C, Beckage B, Perkins T, Keeton WS (2011) Species shifts in response to climate change: individual or shared responses? J Torrey Botanical Soc 138:156–176CrossRefGoogle Scholar
  27. Sankaran M, Hannan NP, Scholes RJ, Ratnam J, Augustine DJ, Cade BS, Gignoux J, Higgins SI, Le Roux X, Ludwig F, Ardo J, Banyukwa F, Bronn A, Bucini G, Caylor KK, Coughenour MB, Diouf A, Ekaya W, Feral CJ, February EC, Frost PGH, Hiernaux P, Hrabar H, Metzger KL, Prins HHT, Ringrose S, Sea W, Tews J, Worden J, Zambatis N (2005) Determinants of woody cover in African savannas. Nature 438:846–849PubMedCrossRefGoogle Scholar
  28. Schenk HJ, Jackson RB (2002) Rooting depths, lateral root spread and below-ground/above-ground allometries of plants in water-limited ecosystems. J Ecol 90:480–494CrossRefGoogle Scholar
  29. Shackleton C (2002) Nearest-neighbour analysis and the prevalence of woody plant competition in South African savannas. Plant Ecol 158:65–76CrossRefGoogle Scholar
  30. Specht RL, Specht A (1999) Australian plant communities: dynamics of structure, growth and biodiversity. Oxford University Press, MelbourneGoogle Scholar
  31. R Development Core Team (2011) R: a language and environment for statistical computing. R Foundation for Statistical ComputingGoogle Scholar
  32. Throop HL, Reichmann LG, Sala OE, Archer SR (2012) Response of dominant grass and shrub species to water manipulation: an ecophysiological basis for shrub invasion in a Chihuahuan Desert Grassland. Oecologia 169:373–383PubMedCrossRefGoogle Scholar
  33. Watson PJ, Bradstock RA, Morris EC (2009) Fire frequency influences composition and structure of the shrub layer in an Australian sub-coastal temperate grassy woodland. Austral Ecol 34:218–232CrossRefGoogle Scholar
  34. Wills KE, Clarke PJ (2008) Plant trait-environmental linkages among contrasting landscapes and climate regimes in temperate eucalypt woodlands. Aust J Bot 56:422–432CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  • Rebecca K. Gibson
    • 1
  • Ross A. Bradstock
    • 1
  • Trent D. Penman
    • 1
  • David A. Keith
    • 2
  • Don A. Driscoll
    • 3
  1. 1.Centre for Environmental Risk Management of Bushfires, Institute for Conservation Biology and ManagementUniversity of WollongongWollongongAustralia
  2. 2.Office of Environment and HeritageNSW GovernmentHurstvilleAustralia
  3. 3.ARC Centre of Excellence for Environmental Decisions, The NERP Environmental Decisions Hub, Fenner School of Environment and SocietyAustralian National UniversityCanberraAustralia

Personalised recommendations